Scenario - 2 GB switches on different floors about 20m apart. I need to link them.
Should I
- just run copper cables between them? If so, how many?
- run fibre between them and use media converters?
- replace with new switches and internal SFP modules and run fibre?
There would be about 15 users on each floor. Cost is not a huge problem.
TIA,
Colm
Running fiber between them using media converters is the worst idea of any of those as it costs as much as buying SFP modules...
The best idea here is to run copper cable(s).
That said I would typically, highly-advise against running more than one cable with cheap equipment as you are NOT going to make it any faster, but you may create a network loop making it where the entire LAN is flooding itself with storm of network frames to the point it is down. Of course, a LOT of better network equipment has loop-protect and Spanning Tree Protocol, which actually works and will put a port into blocking state.
That said, you probably still want to use something like PVST+; since, by default spanning-tree 802.1q takes up to 30 seconds to come to convergence during which time the port will flop through the states blocking, listening, learning, forwarding.
Connecting two (2) switches together with two (2) cables will likely result in spanning-tree blocking one port:
Switch Output:
Switch#sh spanning-tree
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 32769
Address 0090.2B99.D1E9
Cost 19
Port 1(FastEthernet0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
Address 00E0.A34D.1DE3
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 20
Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi0/1 Root FWD 19 128.1 P2p
Gi0/2 Altn BLK 19 128.2 P2p
If you want to do Link Aggregation, you need to create a LAG or Channel-Group
Switch1(config)#
int range gi 0/1 - 2
Switch1(config-if-range)#
channel-group 1 mode desirable
Switch1(config-if-range)#
Creating a port-channel interface Port-channel 1
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to down
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/2, changed state to down
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/2, changed state to up
********
Switch2(config)#
int range gi 0/1 -2
Switch2(config-if-range)#
channel-group 1 mode desirable
Creating a port-channel interface Port-channel 1
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to down
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/2, changed state to down
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/2, changed state to up
%LINK-5-CHANGED: Interface Port-channel 1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Port-channel 1, changed state to up
Switch1#
sh etherchannel port-channel
Channel-group listing:
----------------------
Group: 1
----------
Port-channels in the group:
---------------------------
Port-channel: Po1
------------
Age of the Port-channel = 00d:00h:03m:04s
Logical slot/port = 2/1 Number of ports = 2
GC = 0x00000000 HotStandBy port = null
Port state = Port-channel
Protocol =
PAGP
Port Security = Disabled
Ports in the Port-channel:
Index Load Port EC state No of bits
------+------+------+------------------+-----------
0 00 Gi0/1 Desirable-Sl 0
0 00 Gi0/2 Desirable-Sl 0
Time since last port bundled: 00d:00h:03m:04s Gi0/2
Now, here is the thing... If you are mixing and matching between brands, make certain to use LACP and NOT PAGP (Cisco Only)
*****************
I really doubt you will have an Ethernet fabric with rbridges & trill switches, but if you really have devices that support ISL links and can negotiate Layer-2 routing paths via TRILL ... then everything I posted above is irrelevant... just connect it.
